/python-y86

Assembler and Pipelined Simulator written in Python for Y86, an x86-like ISA from CS:APP

Primary LanguagePythonGNU General Public License v3.0GPL-3.0

Python Y86 Utility

Copyright (c) 2012 Linus Yang


The Python Y86 utility includes an assembler "yas" and a pipelined simulator "pipe" for Y86 (a simplified x86-like ISA described in CMU's CSAPP).

The utility is written in Python and fully compatible with Shedskin, an RPython to C++ compiler, which can compile the Python script into binary executables to improve performance significantly.

Type "-h" to show help and available options.

Y86 Assembler

The Python Y86 assember behaves like the CSAPP official "yas" assembler, which can generate two kinds of Y86 object file, ASCII object and binary object in the same folder of ".ys" assembly source.

The ASCII object ".yo" file is fully compatible with the CSAPP official "yis" or "psim" simulator and friendly to read.
The binary object ".ybo" file is generated for the pipelined simulator to execute.

Features:

  • Support all instructions of Y86 ISA including "iaddl", "leave" and "cmovXX"
  • Support labeling and pseudo instructions, e.g. positioning by ".pos" and code alignment by ".align"
  • Large memory address support which can generate large size object files
  • Fully compatible with Shedskin
  • Flexible options to specify:
    • Object generation using big-endian or little-endian
    • Using rules in CSAPP 1st editon or 2nd edtion

Pipelined Y86 Simulator

The Python pipelined Y86 simulator also behaves like the official "psim" simulator. But it uses binary object ".ybo" generated by "Python Y86 assember" as input.

After execution, the simulator will show brief running results on the screen and generate a log file of each cycle running status. The log syntax is like the official 2nd edtion "psim" simulator output.

Features:

  • Support all instructions of Y86 ISA including "iaddl", "leave" and "cmovXX"
  • Could deal with all "hazard" conditions mentioned on CSAPP
  • Logging with detailed running information of every cycle
  • Fully compatible with Shedskin
  • Flexible options to specify:
    • Object generation using big-endian or little-endian
    • Using rules in CSAPP 1st edition or 2nd edition
    • Setting max running cycles to avoid endless loop

License

This program is distributed under GPLv3.